In the past, in a retail store such as a supermarket, in order to reduce disposal losses of perishables, commodities are sold at discounted prices when the closing time approaches. In this case, the store affixes a label on which benefit content related to commodity purchase such as a discount amount is indicated (hereinafter referred to as benefit indication label) to a predetermined position of a commodity to clearly indicate to customers that the commodity is a discount target commodity. When a benefit indication label is affixed to a commodity to be purchased by a customer, an operator of a POS (Point Of Sales) terminal reads a barcode of the commodity with a scanner and operates a keyboard, a touch panel, or the like to provide a benefit (a discount, etc.) corresponding to the benefit indication label.
Concerning reading of a barcode, there is known a technique for picking up an image of a barcode and a benefit indication label using an image sensor such as a CCD (Charge Coupled Device) and outputting information concerning a commodity code, a discount, and the like read from the picked-up image to a POS terminal to automatically perform discount processing in the POS terminal.
However, in the related art explained above, if a false benefit indication label is affixed to an irregular position by a malicious customer or the like, it is likely that the benefit indication label is processed as a regular benefit indication label.